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Class org.netlib.lapack.DLASQ2

java.lang.Object
   |
   +----org.netlib.lapack.DLASQ2

public class DLASQ2

extends Object

DLASQ2 is a simplified interface to the JLAPACK routine dlasq2.
This interface converts Java-style 2D row-major arrays into
the 1D column-major linearized arrays expected by the lower
level JLAPACK routines.  Using this interface also allows you
to omit offset and leading dimension arguments.  However, because
of these conversions, these routines will be slower than the low
level ones.  Following is the description from the original Fortran
source.  Contact seymour@cs.utk.edu with any questions.

 *     ..
 *
 *     Purpose
 *     =======
 *
 *     DLASQ2 computes the singular values of a real N-by-N unreduced
 *     bidiagonal matrix with squared diagonal elements in Q and
 *     squared off-diagonal elements in E. The singular values are
 *     computed to relative accuracy TOL, barring over/underflow or
 *     denormalization.
 *
 *     Arguments
 *     =========
 *
 *  M       (input) INTEGER
 *          The number of rows and columns in the matrix. M >= 0.
 *
 *  Q       (output) DOUBLE PRECISION array, dimension (M)
 *          On normal exit, contains the squared singular values.
 *
 *  E       (workspace) DOUBLE PRECISION array, dimension (M)
 *
 *  QQ      (input/output) DOUBLE PRECISION array, dimension (M)
 *          On entry, QQ contains the squared diagonal elements of the
 *          bidiagonal matrix whose SVD is desired.
 *          On exit, QQ is overwritten.
 *
 *  EE      (input/output) DOUBLE PRECISION array, dimension (M)
 *          On entry, EE(1:N-1) contains the squared off-diagonal
 *          elements of the bidiagonal matrix whose SVD is desired.
 *          On exit, EE is overwritten.
 *
 *  EPS     (input) DOUBLE PRECISION
 *          Machine epsilon.
 *
 *  TOL2    (input) DOUBLE PRECISION
 *          Desired relative accuracy of computed eigenvalues
 *          as defined in DLASQ1.
 *
 *  SMALL2  (input) DOUBLE PRECISION
 *          A threshold value as defined in DLASQ1.
 *
 *  SUP     (input/output) DOUBLE PRECISION
 *          Upper bound for the smallest eigenvalue.
 *
 *  KEND    (input/output) INTEGER
 *          Index where minimum d occurs.
 *
 *  INFO    (output) INTEGER
 *          = 0:  successful exit
 *          < 0:  if INFO = -i, the i-th argument had an illegal value
 *          > 0:  if INFO = i, the algorithm did not converge;  i
 *                specifies how many superdiagonals did not converge.
 *
 *  =====================================================================
 *
 *     .. Parameters ..

DLASQ2()

DLASQ2(int, double[], double[], double[], double[], double, double, double, doubleW, intW, intW)

 public DLASQ2()

 public static void DLASQ2(int m,
                           double q[],
                           double e[],
                           double qq[],
                           double ee[],
                           double eps,
                           double tol2,
                           double small2,
                           doubleW sup,
                           intW kend,
                           intW info)

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